Existing Code Division Multiple Access (CDMA)-based cellular network technologies achieve what is often referred to as uplink macro-diversity through the use of the well-known “soft handoff” mechanism. In soft handoff mechanism, uplink frames at the link layer or Media Access Control (MAC) sublayer that are transmitted by a user's wireless communication device or mobile terminal are received at multiple base station transceivers as controlled by a separate controlling element, e.g., a Radio Network Controller (RNC) or Base Station Controller (BSC), which is typically more centrally located in the radio access network. The set of receiving base station transceivers forward the uplink frames to the controlling element, which then uses techniques such as frame selection or soft combining, as well as automatic repeat request (ARQ) mechanisms in an attempt to reconstruct and correctly receive the frames sent from the user's wireless communication device. This design has evolved primarily in support of circuit-switch applications, e.g., voice, and is not well-suited for packet-switched networking/internetworking The concentration of information through the controlling element reduces network scalability and also increases the reliability requirements, and cost, of the controlling element. The design also imposes timing, synchronization, and communication latency requirements between the base station transceivers and/or between the base station transceivers and the controlling element.
These requirements are overly restrictive for many packet-switched network/internetwork technologies. In connectionless, packet-switched networks/internetworks such as those based on the Internet Protocol (IP), a sequence of packets (or packet flow) sent from a source node to a destination node need not follow the same path throughout the network/internetwork. It is also generally desirable to confine the dynamics of a specific air-link interface technology to the interface itself, thereby allowing network layer intelligence to be brought forward to the edge of the fixed infrastructure.